The invention relates generally to air data sensing systems to be used in conjunction with air vehicle flight performance computer systems, and, in particular, to air turbulence and wind shear detection systems.
Wind shear involves rapidly changing wind conditions in which wind velocity and direction may vary substantially over short distances or short time intervals. Wind shear creates particular hazards to air vehicles during takeoffs and approaches for landing. A rapidly decreasing head wind causes significant loss of lift, which is dangerous during takeoff or landing when air speed is low and the air vehicle's angle of attack is high. Sudden down drafts disrupt the climb of the air vehicle.
It is desirable to warn the pilot and/or send a signal to a flight control computer as the air vehicle is entering an area of increasing wind shear. The pilot or computer can then increase air vehicle power and also change air vehicle angle of attack as the air vehicle enters into an area of increasing wind shear. Both ground-based and airborne wind shear detection systems are currently known, and while it is desirable to determine hazardous wind shear conditions as soon as possible, oversensitivity generates excess nuisance or false warnings. Indications of wind shear without producing unnecessary warnings remain a desired goal.